Motor assembly for vehicle air conditioner

ABSTRACT

A motor holder or a lower case defines therein a circuit accommodating chamber for accommodating a control circuit device. A side wall of the motor holder or the lower case that defines the circuit accommodating chamber has a vent for ventilating the chamber. A boundary section is formed between the motor holder and the lower case. An overhang extends from the motor holder. In a section of the circumference of the lower case, the overhang continuously covers the boundary section along the outer surface of the side wall of the lower case. A bulging portion is arranged to prevent water droplets from reaching the vent from the overhang. Therefore, the motor assembly prevents the integrally assembled control circuit device from being wet.

BACKGROUND OF THE INVENTION

[0001] The present invention relates to a motor assembly for a vehicleair conditioner, which assembly includes a motor and a control circuitdevice integrally assembled with the motor. More particularly, thepresent invention pertains to a motor assembly for a vehicle airconditioner, which assembly has a structure that prevents a controlcircuit device from being wet.

[0002] For example, Japanese Patent No. 3157567 discloses a motorassembly for a vehicle air conditioner, which assembly includes a motorand a fan. The motor drives rotary shaft that protrudes upward. The fanis coupled to the rotary shaft. As the rotary shaft rotates, the fancauses air above to flow in radially outward directions. In such a motorassembly, the motor is located in an air conditioning chamber whilebeing held by a motor holder. The motor assembly creates airflow in theair conditioning chamber with the fan, thereby drawing air outside orinside the vehicle and sending the air into the passenger compartment.The above described patent publication discloses a structure forpreventing the interior of the motor from being wet.

[0003] On the other hand, to improve the passenger comfort, the rotationspeed of the motor needs to be arbitrarily controlled. The rotationspeed of the motor is controlled by a switching device such as a powertransistor and a MOS field effect transistor (FET). When the motorrotation speed is controlled by using a switching device, a protectioncircuit for protecting the switching device needs to be provided tosecurely control the current (or voltage) of the motor assembly.

[0004] Japanese Laid-Open Patent Publication No. 2000-316247 discloses amotor assembly for a vehicle air conditioner, which assembly has acontrol circuit device and a fan. The assembly also includes a blowercase attached to an upper side of a motor holder, and a lower caseattached to a lower side of the motor holder. A waterproof structure ofthe motor assembly is constructed by providing a notch in a boundarysection between the motor holder and the lower case. If air that hasbeen drawn into the motor assembly contains water, some of the wateradvances along the gap between the motor holder and the lower case, andis then guided to the outside of the motor assembly through the notchformed in the boundary section. As a result, the control circuit deviceis prevented from being wet with water that enters inside the motorassembly.

[0005] However, in the motor assembly disclosed in the publication No.2000-316247, the notch in the boundary section produces a hole.Therefore, if water fails to be guided to the outside of the assemblythrough the notch, the water can enter the interior of the motor andcause the control circuit device to be wet. Further, water that exitsthe assembly through the boundary section can flow along the outersurface of the motor holder or the lower case, and enter the motorthrough the hole, causing the control circuit device to be wet.

[0006] Further, water that exits the assembly through the boundarysection between the blower case and the motor holder can flow along theouter surface of the motor holder, and enter the interior through theboundary section between the motor holder and the lower case, causingthe control circuit device to be wet.

[0007] The motor is located in a position that communicates with anoutside air inlet. Thus, when, the vehicle is washed in a car wash andwater is applied to the outside air inlet with a high pressure, thewater can enter the outside air inlet. This causes connecting memberssuch as wires that electrically connect the control circuit device withthe motor to be wet with water droplets. Further, in some casescondensation occurs due to the difference between the temperature of thepassenger compartment and the outside temperature, which can result inwater droplets collected on the connecting members. The water dropletson the connecting members can then flow along the members and reach thecontrol circuit device.

SUMMARY OF THE INVENTION

[0008] Accordingly, it is an objective of the present invention toprovide a motor assembly for a vehicle air conditioner, which assemblyprevents an integrally assembled control circuit device from being wet.

[0009] To achieve the above objective, the present invention provides amotor assembly for a vehicle air conditioner. The motor assemblyincludes a motor having a rotary shaft, a control circuit device thatcontrols the motor to rotate, a fan fixed to the rotary shaft, a motorholder for accommodating the motor, a lower case attached to the motorholder. The motor holder or the lower case defines therein a circuitaccommodating chamber for accommodating the control circuit device. Aside wall of the motor holder or the lower case that defines the circuitaccommodating chamber has a vent for ventilating the circuitaccommodating chamber. A boundary section is formed between the motorholder and the lower case. An overhang extends from the motor holder.The overhang is integrally formed with the motor holder. The overhangfaces an outer surface of the side wall of the lower case. In a sectionof the circumference of the lower case, the overhang continuously coversthe boundary section along the outer surface of the side wall of thelower case. A bulging portion projects from the overhang in a directionaway from the motor holder. The bulging portion is arranged to preventwater droplets from reaching the vent from the overhang.

[0010] According to another aspect of the invention, a motor assemblyfor a vehicle air conditioner is provided. The motor assembly includes amotor having a rotary shaft, a control circuit device that controls themotor to rotate, a fan fixed to the rotary shaft. When rotates, the fandraws air outside or inside the vehicle and sends the air into thepassenger compartment. The motor assembly further includes a motorholder for accommodating the motor, a motor terminal extending from themotor and a connecting member for electrically connecting the motorterminal with the control circuit device. The motor terminal and theconnecting member form an electric path from the motor to the controlcircuit device. An upward extension is provided in part of theconnecting member in the electrical path that is close to the controlcircuit device. The upward extension extends upward with respect to adirection from the motor toward the control circuit device along theelectric path.

[0011] Other aspects and advantages of the invention will becomeapparent from the following description, taken in conjunction with theaccompanying drawings, illustrating by way of example the principles ofthe invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The invention, together with objects and advantages thereof, maybest be understood by reference to the following description of thepresently preferred embodiments together with the accompanying drawingsin which:

[0013]FIG. 1 is a cross-sectional view taken along line I-O-I of FIG. 2,illustrating a motor assembly for a vehicle air conditioner according toone embodiment of the present invention;

[0014]FIG. 2 is a bottom view illustrating the motor assembly of FIG. 1;

[0015]FIG. 3 is an enlarged view illustrating an overhang and a bentportion of the motor assembly shown in FIG. 1;

[0016]FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. 1;

[0017]FIG. 5 is a perspective view illustrating part of the motorassembly of FIG. 1; and

[0018]FIG. 6 is a perspective view illustrating part of a motor assemblyaccording to another embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] One embodiment of the present invention will now be describedwith reference to the drawings.

[0020] As shown in FIG. 1, a motor 1 of a motor assembly for a vehicleair conditioner is a direct-current motor. The motor 1 includes asubstantially cylindrical yoke 2, a brush holder 3, magnets 4 and anarmature 5. The brush holder 3 covers an open end (upper end as viewedin FIG. 1) of the yoke 2 and holds brushes 3 a. The magnets 4 aresecured to the inner circumferential surface of the yoke 2. The armature5 is substantially accommodated in the yoke 2. A rotary shaft 6 of thearmature 5 is rotatably supported with a bearing 7 fixed to the brushholder 3 and with a bearing 8 fixed to the yoke 2 such that one end ofthe rotary shaft 6 protrudes upward from the brush holder 3. The motor 1is arranged in the vehicle such that the axial direction of the rotaryshaft 6 is substantially vertical.

[0021] The armature 5, which is located inside the magnets 4, has a core5 a and a commutator 5 b. The core 5 a is fixed to a section of therotary shaft 6 that is slightly below the middle of the rotary shaft 6.The commutator 5 b is fixed to the section of the rotary shaft 6 that isslightly above the middle of the rotary shaft 6. The brushes 3 a held bythe brush holder 3 slide on the commutator 5 b. A fan 9 is coupled tothe upper end of the rotary shaft 6 to rotate integrally with the rotaryshaft 6. When the rotary shaft 6 rotates, the fan 9 flows air above inradially outward directions. The fan 9 includes a boss 9 a, abell-shaped portion 9 b, an annular portion 9 c, blades 9 d, and acoupling portion 9 e. The rotary shaft 6 is fitted in the boss 9 a. Thebell-shaped portion 9 b extends from the boss 9 a to cover the uppersides of the brush holder 3 and the yoke 2. The annular portion 9 cfurther extends radially outward from the periphery of the bell-shapedportion 9 b. The blades 9 d (only two of which are shown in FIG. 1) arearranged along the circumferential direction of the boss 9 a such thatthe upper end of each blade 9 d is coupled to the annular couplingportion 9 e and the lower end of each blade 9 d is coupled to theannular portion 9 c. When the rotary shaft 6 rotates, the fan 9 causesair above to flow in radially outward direction with the blades 9 d (seesolid arrows in FIG. 1).

[0022] The motor 1 is held by a synthetic resin motor holder 11 and islocated in an air conditioning chamber 12. As shown in FIGS. 1 and 2,the motor holder 11 includes a holding cylinder 11 a and a disk-shapedflange 11 b. The holding cylinder 11 a is substantially shaped as acylinder with a bottom wall. The flange 11 b extends radially outwardfrom an axially central portion of the holding cylinder 11 a. The motor1 (the yoke2) is inserted in and held by the holding cylinder 11 a. Theflat surface of the annular portion 9 c of the fan 9 faces the flange 11b. An air conditioning chamber member (blower case) 13, which is shownwith two-dot chain line in FIG. 1, is fixed to the motor holder 11. Theair conditioning chamber member 13 has a circumferential wall 13 a. Asuction port (not shown) is formed in an upper section of thecircumferential wall 13 a. The suction port communicates with an outsideair inlet and an inside air inlet (not shown). Also, a discharge port(not shown) is formed in a radially outer part of the circumferentialwall 13 a. A space surrounded by the air conditioning chamber member 13and the flange 11 b is the air conditioning chamber 12.

[0023] A circuit board 14 a is fixed to a lower surface 11 d of theflange 11 b with, for example, screws. A number of elements that form acontrol circuit device 14 are mounted to the circuit board 14 a. Whenexcitation current is supplied to the armature 5 from the controlcircuit device 14 through the brushes 3 a, the armature 5 is rotated.Accordingly, the rotary shaft 6 is rotated. The control circuit device14 controls the rotation speed of the rotary shaft 6. Therefore, whenexcitation current is supplied to the armature 5, the fan 9 is rotatedtogether with the rotary shaft 6. Accordingly, air outside or inside thevehicle is drawn and sent to the passenger compartment.

[0024] A through hole 2 a is formed in the bottom of the yoke 2. Thethrough hole 2 a connects the interior of the yoke 2 with the outside.The through hole 2 a communicates with a communication passage 114 thatis defined between the bottom of the holding cylinder 11 a of the motorholder 11 and the bottom of the yoke 2.

[0025] A lower case 15 is fixed to the lower surface 11 d of the flange11 b of the motor holder 11 with, for example, screws. The lower case 15and the motor holder 11 defines an air duct 115 for guiding some of thebrown air created by the fan 9 to the interior of the motor 1 (theinterior of the yoke 2) to cool the motor 1 (see arrows of broken linesin FIG. 1). The lower case 15 accommodates the control circuit device14. The lower case 15 is made of the same synthetic resin as the motorholder 11. The air duct 115 is connected to the through hole 2 a throughthe communication passage 114. The air duct 115 is also connected to anintroduction hole 11 f formed in a radially projecting portion of theflange 11 b.

[0026] A partitioning wall 15 a is located in the lower case 15. Thepartitioning wall 15 a is integrally formed with the lower case 15 toseparate the air duct 115 and the control circuit device 14 from eachother. The partitioning wall 15 a divides the interior;of the lower case15 so that a circuit accommodating chamber 16 is defined between themotor holder 11 and the partitioning wall 15 a. The control circuitdevice 14 is accommodated in the circuit accommodating chamber 16. Thecircuit accommodating chamber 16 does not need to be defined in thelower case 15, but may be defined in the motor holder 11.

[0027] The circumferential wall 13 a of the air conditioning chambermember 13, which surrounds the fan 9, is attached to the upper surfacelie of the flange 11 b. A boundary section 121 between the flange 11 band the circumferential wall 13 a has a small gap.

[0028] As shown in FIGS. 1, 2 and 4, a boundary section 125 is definedbetween the flange 11 b of the motor holder 11 and the lower case 15. Asshown in FIGS. 1 to 4, an overhang 124 is integrally formed with theflange 11 b to extend further downward than the boundary section 125.The overhang 124 covers the outer surface of the side wall of the lowercase 15. The overhang 124 extends as far as the lower end of the sidewall of the lower case 15. That is, the lower end 124 a of the overhang124 reaches the lower end of the side wall of the lower case 15. Theoverhang 124 may extend further downward than the lower end of the sidewall of the lower case 15. The boundary section 125 has a small gap sothat the flange 11 b and the lower case 15 do not closely contact eachother. The overhang 124 continuously covers the gap of the boundarysection 125 from the outside of the lower case 15. That is, the overhang124 is bent to extend in a direction perpendicular to the rotary shaft 6of the motor 1, that is, horizontally to surround the air duct 115(particularly refer to FIGS. 2 and 4). In other words, the overhang 124surrounds part of the lower case 15 that surrounds the air duct 115. Thelongitudinal direction of the overhang 124 is the directionperpendicular to the rotary shaft 6.

[0029] As shown in FIG. 3, a vent 123 is formed in each side wall in thelower case 15 that defines the circuit accommodating chamber 16. Thevents 123 (only one is shown in FIG. 3) are used to dissipate heatgenerated by the control circuit device 14. As shown in FIGS. 2 and 3, abulging portion, which is a curved portion 126 bent outward away fromthe lower case 15, is formed in each horizontal end of the overhang 124,or in each end of the overhang 124 in a direction perpendicular to therotary shaft 6 of the motor 1. That is, each curved portion 126 islocated at an end of the overhang 124 that is adjacent to the vent 123.Each curved portion 126 is arranged such that the corresponding vent 123is at least partly exposed to the outside. In this embodiment, eachcurved portion 126 is arranged along the periphery of the correspondingvent 123. As long as the vents 123 each is formed in a side wall thatdefines the circuit accommodating chamber 16, the vents 123 do not needto be formed in the side wall of the lower case 15, but may be formed inthe side wall of the motor holder 11.

[0030] In the motor assembly for a vehicle air conditioner asconstructed above, when the motor 1 rotates in response to an operationof the control circuit device 14, the fan 9 rotates to blow air as shownin FIG. 1. Some of the airflow created by the rotation of the fan 9flows into the introduction hole 11 f as a coolant air (indicated byarrows in FIG. 1). This portion of the airflow passes through the airduct 115, the communication passage 114, and the communication hole 2 aof the yoke 2 and reaches the interior of the motor 1. Thereafter, theairflow is discharged through an opening between the yoke 2 of the motor1 and the brush holder 3. While passing through the interior of themotor 1, the airflow cools the interior of the motor 1. Specifically,the airflow cools the components of the motor 1, such as the coil of thearmature 5, the brushes 3 a, and the commutator 5 b.

[0031] The boundary section 121 between the flange 11 b and thecircumferential wall 13 a has the small gap so that the flange 11 b andthe circumferential wall 13 a do not closely contact each other.Therefore, if the fan 9 draws moisture and droplets (rain, snow)contained in the outside air into the air conditioning chamber 12, someof the drawn water enters the boundary section 121. The water then flowsalong the boundary section 121 and oozes to the outer surface of themotor assembly through the boundary section 121. Since the overhang 124is provided at a section of the motor holder 11 in which the water oozesthrough the boundary section 121, the oozed water flows downward alongthe outer surface of the overhang 124 and drips from the lower end 124 aof the overhang 124.

[0032] The motor assembly can be inclined depending on the state ofoperation. In such a case, water that has oozed to the outer surface ofthe motor assembly through the boundary section 121 can reach the curvedportions 126 after flowing in the longitudinal direction along theoverhang 124, or flowing from right to left in the FIG. 3. Afterreaching any of the curved portions 126, the water is guided by thecurved portion 126 and drips.

[0033] As shown in FIGS. 1 and 2, the motor 1 is electrically connectedto the control circuit device 14 with connecting members, which are twointermediate terminals 21. Each intermediate terminal 21 electricallyconnects the corresponding motor terminal 3 b extending from the motor 1to the control circuit device 14. That is, the motor terminal 3 b andthe intermediate terminal 21 form an electric path from the motor 1 tothe control circuit device 14. Each intermediate terminal 21 is formedby punching a metal plate with a pressing machine, and bending thepressed plate with a pressing machine. Each intermediate terminal 21 isaccommodated in a connecting member accommodating chamber, which is aterminal accommodating chamber 17 defined between the motor holder 11and part of the lower case 15. The terminal accommodating chamber 17 isadjacent to the circuit accommodating chamber 16 with a partition wall(not shown) in between. That is, the terminal accommodating chamber 17is isolated from the circuit accommodating chamber 16. The intermediateterminal 21 is provided on the flange 11 b, and the motor terminal 3 bextends from the motor 1 toward the flange 11 b.

[0034] As shown in FIGS. 1 and 5, the intermediate terminal 21 includesa bent portion 22, which has a U-shaped section. The bent portion 22includes a downward extension 23, a bottom portion 24, and an upwardextension 25. The downward extension 23, the bottom portion 24, and theupward extension 25 are each formed rectangular. The upper end of thedownward extension 23 is bent so that a terminal receiving portion 26 isformed. One end of the motor terminal 3 b (lower end) is fitted in theterminal receiving portion 26. The other end (upper end) of the motorterminal 3 b extends through a through hole 11 c formed in the flange 11b toward the brush holder 3, and is electrically connected to the brush3 a.

[0035] In the electric path, the downward extension 23 is provided in aportion of the intermediate terminal 21 that is closer to the motorterminal 3 b. The downward extension 23 extends downward with respect tothe direction from the motor 1 toward the control circuit device 14along the electric path. The downward extension 23 extends from theterminal receiving portion 26 along the axis of the rotary shaft 6, thatis, extends vertically.

[0036] The bottom portion 24 is bent from the lower end of the downwardextension 23 at a right angle and extends horizontally. The upwardextension 25 extends from the distal end of the bottom portion 24 upwardalong the axis of the rotary shaft 6. That is, in the electric path, theupward extension 25 is provided in a portion of the intermediateterminal 21 that is closer to the control circuit device 14. The upwardextension 25 extends upward with respect to the direction from the motor1 toward the control circuit device 14 along the electric path. Thewidths of the downward extension 23, the bottom portion 24, and theupward extension 25 are substantially the same.

[0037] From an edge of an upper portion of the upward extension 25, aside extension 27 extends along the width of the upward extension 25 ata right angle with respect to the edge. The length from the lower end tothe upper end of the upward extension 25, that is, the length (height)H1 from the bottom portion 24 to the lower end of the side extension 27,is determined such that even if water droplets collect on the bottomportion 24 and move upward due to surface tension, the water droplets donot reach the lower end of the side extension 27. As shown in FIG. 2,the side extension 27 extends from the upward extension 25 toward thecontrol circuit device 14. The side extension 27 is electricallyconnected to the circuit board 14 a (the control circuit device 14) withan engaging portion 28 formed at the distal end of the side extension27.

[0038] When the vehicle is washed in a car wash and rush of water isapplied to the vehicle and when condensation occurs due to thedifference between the temperature of the passenger compartment and theoutside temperature, water droplets collect on the inner surface of theair conditioning chamber member 13 and the upper surface lie of theflange 11 b. Water droplets also collect on the motor terminal 3 b,which is exposed in the upper surface lie of the flange 11 b. In otherwords, the motor terminal 3 b is located at a position where waterdroplet collect. Therefore, water droplets may enter the through hole 11c along the motor terminal 3 b and reaches the intermediate terminal 21.Since the intermediate terminal 21 of this embodiment has the upwardextension 25, which extends upward in a direction from the motor 1toward the control circuit device 14, the droplets are prevented movingupward along the upward extension 25. Thus, the droplets are preventedfrom moving along the intermediate terminal 21 and reaching the controlcircuit device 14. That is, the control circuit device 14 is preventedfrom being wet.

[0039] Further, the downward extension 23 and the bottom portion 24 arelocated in a section preceding the upward extension 25 with respect tothe direction from the motor 1 toward the control circuit device 14.Thus, water droplets that have moved to the downward extension 23 fromthe motor terminal 3 b drop off the lower end of the downward extension23 and the bottom portion 24. Therefore, water droplets hardly reach theupward extension 25, which further effectively prevents droplets fromreaching the control circuit device 14.

[0040] This embodiment provides the following advantages.

[0041] (1) The overhang 124 extends from the flange 11 b of the motorholder 11 to cover the gap of the boundary section 125 between the motorholder 11 and the lower case 15. As a result, water that has oozed tothe outer surface of the motor assembly through the boundary section 121between the flange 11 b and the circumferential wall 13 a dribbles alongthe overhang 124. Therefore, since water hardly enters the interior ofthe motor assembly through the boundary section 125 between the motorholder 11 and the lower case 15, water is prevented from entering thecircuit accommodating chamber 16. The control circuit device 14 istherefore prevented from being wet.

[0042] (2) The curved portions 126 are formed on the overhang 124. Whenwater that moves along the overhang 124 reaches either curved portion126, the water dribbles along the curved portion 126. As a result, wateris prevented from entering the circuit accommodating chamber 16 throughthe vent 123 formed in the side wall of the lower case 15. Therefore,even if water moves on the overhang 124 along the longitudinal directionof the overhang 124, for example, when the motor assembly is used whilebeing inclined, the control circuit device 14 is prevented from beingwet.

[0043] (3) The partitioning wall 15 a is located in the lower case 15 toseparate the air duct 115 and the circuit accommodating chamber 16 fromeach other. As a result, even if the outside air that is drawn insidethe motor assembly contains moisture or water (rain, snow), the outsideair is prevented from entering the circuit accommodating chamber 16 bythe partitioning wall 15 a when passing through the air duct 115.Therefore, the control circuit device 14 is not exposed to air flowcontaining water, and is prevented from being wet.

[0044] (4) The configuration of the above embodiment is simple in whichonly the overhang 124 having the curved portions 126 is provided tocover the boundary section 125 between the motor holder 11 and the lowercase 15. This facilitates the manufacturing and does not increase thecosts.

[0045] (5) Since the motor holder 11 and the overhang 124 areintegrated, no sealing member is needed to be provided at the boundarysection 125 between the motor holder 11 and the lower case 15 to preventwater from entering the assembly. As a result, no extra cost isrequired.

[0046] (6) The overhang 124 only covers a portion of the lower case 15that are likely to be wet. This configuration prevents unnecessaryincrease of the weight. Further, the vent 123 formed in the side wall ofthe circuit accommodating chamber 16 is not blocked. The vent 123 isthus not hindered from dissipating heat of the control circuit device14.

[0047] (7) The motor terminal 3 b is located at a position where waterdroplets are likely to collect. In a section of the intermediateterminal 21 that is close to the control circuit device 14, the upwardextension 25, which extends upward with respect to the direction fromthe motor 1 toward the control circuit device 14, is provided to preventwater droplets from moving from the motor terminal 3 b toward thecontrol circuit device 14 (the circuit board 14 a). Thus, even if waterdroplets collect on the intermediate terminal 21, the water droplets areprevented from moving upward along the intermediate terminal 21 andreaching the control circuit device 14. Therefore, the control circuitdevice 14 is prevented from being wet, which improves the reliability ofthe control circuit device 14.

[0048] (8) The downward extension 23 is provided in a portion of theintermediate terminal 21 that is closer to the motor terminal 3 b. Thedownward extension 23 extends downward with respect to the directionfrom the motor 1 toward the control circuit device 14. Thus, waterdroplets that have moved from the motor terminal 3 b drop off the lowerend of the downward extension 23 and the bottom portion 24 between thedownward extension 23 and the upward extension 25. Therefore, waterdroplets hardly reach the upward extension 25, which further effectivelyprevents droplets from reaching the control circuit device 14. Further,since the downward extension 23 and the upward extension 25 form thebent portion 22 in the intermediate terminal 21, vibration of the motor1 transmitted from the motor terminal 3 b is attenuated by the bentportion 22 and is not transmitted to the control circuit device 14.Accordingly, the noise of the motor assembly for the vehicle airconditioner is reduced, and the reliability of the control circuitdevice 14 is improved.

[0049] (9) The length H1 from the lower end to the upper end of theupward extension 25 of the intermediate terminal 21, that is, the lengthfrom the bottom of the upward extension 25 to the lower end of the sideextension 27, is determined such that even if water droplets move upwarddue to surface tension, the droplets do not reach the lower end of theside extension 27. Therefore, water droplets are further effectivelyprevented from moving upward along the upward extension 25 and reachingthe control circuit device 14.

[0050] (10) The upward extension 25 of the intermediate terminal 21 isformed along the axis of the rotary shaft 6 such that the upwardextension 25 extends along the vertical direction when the motorassembly is mounted to the vehicle. Therefore, water droplets arefurther effectively prevented from moving upward along the upwardextension 25 and reaching the control circuit device 14.

[0051] (11) The downward extension 23 of the intermediate terminal 21 isformed along the axis of the rotary shaft 6 such that the downwardextension 23 extends along the vertical direction when the motorassembly is mounted to the vehicle. Then, droplets more easily drop offthe lower end of the downward extension 23. Therefore, water dropletshardly reach the upward extension 25, which further effectively preventsdroplets from reaching the control circuit device 14.

[0052] (12) Since the circuit accommodating chamber 16 and the terminalaccommodating chamber 17 are defined, water droplets on the intermediateterminal 21 are prevented from collecting on the terminal accommodatingchamber 17, and water droplets on the terminal accommodating chamber 17are prevented from collecting on the circuit accommodating chamber 16.Therefore, the control circuit device 14 is further effectivelyprevented from being wet.

[0053] (13) If the specifications of the motor 1 is modified (the shapeis modified), the motor 1 can be connected to the control circuit device14 only by changing the shape of the intermediate terminal 21, and theshape of the control circuit device 14 does not need to be modified.Therefore, even if the specification of the motor 1 is modified, thesame control circuit device 14 can be used. This reduces the costs ofthe control circuit device 14.

[0054] The invention may be embodied in the following forms.

[0055] In the illustrated embodiment, the bulging portions forpreventing water from entering the circuit accommodating chamber 16 fromthe vent 123 formed in the side wall of the circuit accommodatingchamber 16 comprise the curved portions 126 formed by bending the endsof the overhang 124. However, the bulging portions may be formed on theoverhang 124 by molding.

[0056] In the illustrated embodiment, the partitioning wall 15 a isintegrally formed with the lower case 15. However, the partitioning wall15 a may be separately formed from the lower case 15. Alternatively, thepartitioning wall 15 a may be integrally formed with the motor holder11. If the partitioning wall 15 a is integrally formed with the lowercase 15 or the motor holder 11, the number of the components is reduced,and the load of the assembly is reduced.

[0057] The upward extension 25 does not need to extend along the axis ofthe rotary shaft 6, but may be extend slantly upward with respect to theaxis of the rotary shaft 6. That is, the orientation of the upwardextension 25 may be varied as long as the distal end of the upwardextension 25 heads upward than the proximal end of the upward extension25, which is connected to the bottom portion 24, when the motor assemblyis mounted to the vehicle.

[0058] In the illustrated embodiment, the intermediate terminal 21includes the downward extension 23, the bottom portion 24, and theupward extension 25. This configuration may be changed as long as theintermediate terminal 21 at least has the upward extension 25. Thebottom portion 24 may be omitted, and at least one of the upwardextension 25 and the downward extension 23 may be inclined. The upwardextension 25 does not need to be shaped a flat plate.

[0059] In the illustrated embodiment, the intermediate terminal 21 isused as a connecting member. However, as shown in FIG. 6, a connectingwire 31 may be used as a connecting member. The connecting wire 31 has abent portion 34. The bent portion 34 is substantially shaped as theletter U and includes a downward extension 32 and an upward extension33. The downward extension 32 extends downward with respect to the motorterminal 3 b, and the upward extension 33 extends upward form the lowerend of the downward extension 32. A terminal receiving member 35 isattached to the upper end of the downward extension 32. The motorterminal 3 b is fitted in the terminal receiving member 35.

[0060] In the above illustrated embodiment, the accommodating chamber 16for accommodating the control circuit device 14 and the terminalaccommodating chamber 17 for accommodating the intermediate terminal 21are defined. However, the circuit accommodating chamber 16 and theterminal accommodating chamber 17 need not be defined.

[0061] In the illustrated embodiment, the motor 1 is mounted to thevehicle such that the axial direction of the rotary shaft 6 is vertical.However, the motor 1 may be mounted to the vehicle such that the axialdirection of the rotary shaft 6 is slightly inclined with respect to thevertical direction.

[0062] In the illustrated embodiment, the motor 1 has the brushes 3 a.However, the present invention may be applied to a brushless motor. Inthis case also, the same advantages as listed above are provided.

[0063] The present examples and embodiments are to be considered asillustrative and not restrictive and the invention is not to be limitedto the details given herein, but may be modified within the scope andequivalence of the appended claims.

1. A motor assembly for a vehicle air conditioner, comprising: a motorhaving a rotary shaft; a control circuit device that controls the motorto rotate; a fan fixed to the rotary shaft; a motor holder foraccommodating the motor; a lower case attached to the motor holder,wherein the motor holder or the lower case defines therein a circuitaccommodating chamber for accommodating the control circuit device, aside wall of the motor holder or the lower case that defines the circuitaccommodating chamber has a vent for ventilating the circuitaccommodating chamber, a boundary section being formed between the motorholder and the lower case; an overhang that extends from the motorholder, the overhang being integrally formed with the motor holder,wherein the overhang faces an outer surface of the side wall of thelower case, and wherein, in a section of the circumference of the lowercase, the overhang continuously covers the boundary section along theouter surface of the side wall of the lower case; and a bulging portionthat projects from the overhang in a direction away from the motorholder, wherein the bulging portion is arranged to prevent waterdroplets from reaching the vent from the overhang.
 2. The motor assemblyaccording to claim 1, wherein the bulging portion is arranged along theperiphery of the vent.
 3. The motor assembly according to claim 1,wherein the bulging portion is located at an end of the overhang that isadjacent to the vent.
 4. The motor assembly according to claim 1,wherein the bulging portion is arranged such that at least part of thevent is exposed to the outside.
 5. The motor assembly according to claim1, wherein the bulging portion is located at an end of the overhang withrespect to a direction perpendicular to the rotary shaft.
 6. The motorassembly according to claim 1, wherein the bulging portion is a curvedportion that is formed by bending an end of the overhang away from thelower case.
 7. The motor assembly according to claim 1, wherein theoverhang extends at least as far as a lower end of the side wall of thelower case.
 8. The motor assembly according to claim 1, wherein thelower case covers the motor holder from below, and the lower case andthe motor holder define an air duct, wherein, when the rotary shaftrotates, the fan is rotated accordingly and generates cooling airflow,and wherein the air duct guides the cooling airflow to the motor to coolthe motor.
 9. The motor assembly according to claim 8, furthercomprising a partitioning wall that separates the air duct from thecircuit accommodating chamber.
 10. The motor assembly according to claim8, wherein the overhang covers part of the circumference of the lowercase that surrounds the air duct.
 11. A motor assembly for a vehicle airconditioner, comprising: a motor having a rotary shaft; a controlcircuit device that controls the motor to rotate; a fan fixed to therotary shaft, wherein, when rotates, the fan draws air outside or insidethe vehicle and sends the air into the passenger compartment; a motorholder for accommodating the motor; a motor terminal extending from themotor; and a connecting member for electrically connecting the motorterminal with the control circuit device, the motor terminal and theconnecting member forming an electric path from the motor to the controlcircuit device, wherein an upward extension is provided in part of theconnecting member in the electrical path that is close to the controlcircuit device, the upward extension extending upward with respect to adirection from the motor toward the control circuit device along theelectric path.
 12. The motor assembly according to claim 11, wherein themotor holder includes a holding cylinder and a flange, the motor beinginserted in and held by the holding cylinder, the flange extendingradially outward from the holding cylinder, wherein the connectingmember is provided on the flange, and the motor terminal extends fromthe motor toward the flange.
 13. The motor assembly according to claim11, wherein, when the motor assembly is mounted to the vehicle, theupward extension extends substantially vertically.
 14. The motorassembly according to claim 11, wherein a downward extension is providedin part of the connecting member in the electric path that is close tothe motor terminal, the downward extension extending downward withrespect to a direction from the motor toward the control circuit devicealong the electric path.
 15. The motor assembly according to claim 14,wherein, when the motor assembly is mounted to the vehicle, the downwardextension extends substantially vertically.
 16. The motor assemblyaccording to claim 11, wherein the length of the upward extension isdetermined such that if water droplets on the lower end of the upwardextension move upward along the upward extension due to surface tension,the water droplets do not reach the upper end of the upward extension.17. The motor assembly according to claim 11, wherein the motor holderdefines a circuit accommodating chamber for accommodating the controlcircuit device and a connecting member accommodating chamber foraccommodating the connecting member, one of the accommodating chambersbeing isolated from the other accommodating chamber.
 18. A motorassembly for a vehicle air conditioner, comprising: a motor having arotary shaft; a control circuit device that controls the motor torotate; a fan fixed to the rotary shaft, wherein, when rotates, the fandraws air outside or inside the vehicle and sends the air into thepassenger compartment; a motor holder for accommodating the motor; alower case attached to the motor holder, wherein the motor holder or thelower case defines therein a circuit accommodating chamber foraccommodating the control circuit device, a side wall of the motorholder or the lower case that defines the circuit accommodating chamberhas a vent for ventilating the circuit accommodating chamber, a boundarysection being formed between the motor holder and the lower case; anoverhang that is extended from the motor holder, the overhang beingintegrally formed with the motor holder, wherein the overhang faces anouter surface of the side wall of the lower case, and wherein, in asection of the circumference of the lower case, the overhangcontinuously covers the boundary section along the outer surface of theside wall of the lower case; a bulging portion that projects from theoverhang in a direction away from the motor holder, wherein the bulgingportion is arranged to prevent water droplets from reaching the ventfrom the overhang; a motor terminal extending from the motor; and aconnecting member for electrically connecting the motor terminal withthe control circuit device, the motor terminal and the connecting memberforming an electric path from the motor to the control circuit device,wherein an upward extension is provided in part of the connecting memberin the electrical path that is close to the control circuit device, theupward extension extending upward with respect to a direction from themotor toward the control circuit device along the electric path.
 19. Themotor assembly according to claim 18, wherein the overhang extends atleast as far as a lower end of the side wall of the lower case.
 20. Themotor assembly according to claim 18, wherein a downward extension isprovided in part of the connecting member in the electric path that isclose to the motor terminal, the downward extension extending downwardwith respect to a direction from the motor toward the control circuitdevice along the electric path.